A variety of enclosure types are known. Many are configured for containing active electrical and electronic equipment, for example, which is used in hazardous environments. When intended for this purpose many are explosion-proof.
Typically, an issue with hazardous environments is that a spark or flame could ignite flammable gasses or other constituents in the operating environment. Explosion-proof housings are designed and constructed to meet industry standards such as the explosion-proof standards contained in the National Electrical Code (NEC). Explosion-proof enclosures, such as a cast box, generally comprise a first housing portion which contains the active electrical and electronic instrument or device, and a second housing portion attached to the first housing portion to fully enclose the device. The first and second housing portions are secured to provide containment to any internal flammable events that originate inside the enclosure.
An explosion-proof enclosure is configured to allow gases from inside the enclosure to escape across joints of the enclosure and cool as the gases exit the explosion-proof enclosure. The joints are also known as flame paths and exist where two surfaces meet and provide a path from inside the explosion-proof enclosure to outside the explosion-proof enclosure, along which one or more gases may travel. A joint may be a mating of any two or more surfaces.
A few notable issues with conventional explosion-proof enclosures include the following: (1) first and second housing portions of an explosion-proof enclosure are often secured to one another with bolts; which can be less convenient for obtaining access; (2) explosion-proof enclosures contain complex components for operating electrical devices housed therein making the cost of manufacturing higher; (3) explosion-proof enclosures can be large and heavy to move safely or hard to open once mounted in place; and (4) explosion-proof enclosures may be exposed to corrosive conditions such that after a period of time it may be difficult to open the explosion-proof enclosures leading to forced, unsafe, openings.
Improvements in enclosures are desirable. The improvements characterized herein are particularly well adapted for explosion-proof enclosures, but are applicable with other types of enclosures.